urlReferrer将在MVC Post controller Action Method中变为null

我是张贴表单从一个mvc应用程序A到另一个mvc应用程序b

在B动作方法我得到urlReferer为空。

应用A代码:

 private string BuildPostForm(string Url, string PostData)
        {
            try
            {
                string formId = "__PostForm";
                StringBuilder strForm = new StringBuilder();
                strForm.Append(string.Format("<form id='"{0}'" name='"{0}'" action='"{1}'" method='"POST'">", formId, Url));
                string MID = "9820359248";
                strForm.Append("<input type='"hidden'" name='"" + "merchantRequest" + "'" value='"" + PostData + "'">");
                strForm.Append("<input type='"hidden'" name='"" + "MID" + "'" value='"" + MID + "'">");
                //if (PostData != null)
                //{
                //    foreach (string key in PostData)
                //    {
                //        strForm.Append("<input type='"hidden'" name='"" + key + "'" value='"" + PostData[key] + "'">");
                //    }
                //}
                //  strForm.Append("<div id='"loading'"><p class='"top1 loading-txt'"> Processing Payment </p><img id='"loading-image'" src='"../../Images/ajax-loader.gif'"   alt='"Loading...'" /><p class='"top2 loading-txt-bottom'">Please do not press on refresh button</p></div>");
                strForm.Append("<div class='"wrapper'"><div class='"login_wrap loading_wrap'"><div class='"logo'"> </div><br><p class='"top1 loading-txt'"> Processing Payment  </p><div class='"sk-spinner sk-spinner-wandering-cubes loading_tp'"><div class='"sk-cube1'"></div><div class='"sk-cube2'"></div></div><p  class='"top2 loading-txt-bottom'">Please do not press on refresh button</p></div></div>");
                strForm.Append("</form>");
                strForm.Append("<link  rel='"stylesheet'" href='"../../Content/css/PinePGRedirect.css'" type='"text/css'"/>");
                strForm.Append("<link  rel='"stylesheet'" href='"../../Content/css/loader.css'" type='"text/css'"/>");
                StringBuilder strScript = new StringBuilder();
                strScript.Append("<script language='"javascript'">");
                strScript.Append(string.Format("var v{0}=document.{0};", formId));
                strScript.Append(string.Format("v{0}.submit();", formId));
                strScript.Append("</script>");
                return strForm.ToString() + strScript.ToString();
            }
            catch (Exception ex)
            {
                return null;
            }
        }
     public override void ExecuteResult(ControllerContext context)
        {
            var strHtml = "";
                strHtml = BuildPostForm(m_Url, m_strPostData);
            context.HttpContext.Response.Write(strHtml);
        }

程序B代码:

        [HttpPost]
        public ActionResult Index(FormCollection formCollection)
        {
            try
            {
                Uri uri1 =  HttpContext.Request.UrlReferrer;
               string str =  Request.ServerVariables["HTTP_REFERER"];
}
catch(Exception ex)
{
}
return View();
}